[require] GLSL >= 1.20 [vertex shader file] glsl-mvp.vert [fragment shader] #version 120 void main() { const float x = max(0.25, -5.0); const vec2 v = max(vec2(0.5, 0.2), 0.25); gl_FragColor = vec4(x, v, 1.0); } [test] clear color 0.0 0.0 0.0 0.0 clear ortho draw rect 10 10 10 10 probe rgb 15 15 0.25 0.5 0.25